Clothes washing machine with a slipping clutch



April 18, 1967 J. R. FOSLER ETAL 3,314,257

CLOTHES WASHING MACHINE WITH A SLIPPING CLUTCH Filed Feb. 4, 1965 3 Sheets-Sheet l INVENTORA. John R. Fos/er Ver/os 6. Sharpe The/r Afforn e y April 18, 1967 J. R. FOSLER ETAL 3,314,257

CLOTHES WASHING MACHINE WITH A SLIPPING CLUTCH Filed Feb. 4, 1965 5 Sheets-Sheet 2 INVENTORS John R. Fos/er BY l/erlos 6. Sharpe The/r A/forney April 18, 1967 J. R. FOSLER ETAL CLOTHES WASHING MACHINE WITH A SLIPPING CLUTCH 5 Sheets-Sheet 5 Filed Feb. 4, 1965 Fig. 6

INVENTORS John R. Fos/er BY l/er/os G. Sharpe Their A/forney United States Patent 3,314,257 CLO'IIES WASHING MACHINE WITH A SLIIFING CLUTCH John R. Foster and Verlos G. Sharpe, Dayton, Ohio, as-

signors to General Motors Corporation, Detroit, Mich.,

a corporation of Delaware Filed Feb. 4, 1965, Ser. No. 430,264 13 Claims. (Cl. 68-23) This invention relates to a domestic appliance and more particularly to an improved roller drive mechanism of the type taught in the patent to Brucken 3,087,321, issued April 30, 1963, for agitating and spinning in a clothes washer.

It is a general object of this invention to provide a roller drive agitating and spinning mechanism with a slipping clutch in the power train between the motor and the spin tub of a clothes washer.

It is a further object of this invention to provide an improved roller drive agitating and spinning mechanism havinng means including a gyration limiting resilient mounting arrangement for eliminating the requirement for an out of balance load trip mechanism with the spin tub.

A further object of this invention is the provision of a slipping clutch in a roller drive mechanism which is effective selectively only during spin.

A more particular object of this invention is the provision of a slip clutch means in the spin driving train of a roller drive mechanism, said slip clutch means being slippingly responsive to a torque below the maximum motor torque for slipping to prevent excessive out of balance loads from being carried to spin speeds above the critical.

A further object of this invention is the provision in a roller drive mechanism of an improved slipping clutch to eliminate the need for a capacitor with the drive motor due to low starting torque requirements.

Further objects and advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawings wherein a preferred embodiment of the present invention is clearly shown.

In the drawings:

FIGURE 1 is a sectional view, partly in elevation, of a clothes washer suitable for use with the improved roller drive spinning mechanism of this invention;

FIGURE 2 is a cross-sectional view, partly in elevation, of the improved roller drive agitating and spinning mechanism;

FIGURE 3 is an exploded perspective view of the slipping clutch assembly of this invention;

FIGURE 4 is a fragmentary sectional view taken along line 4--4 in FIGURE 2;

FIGURE 5 is a fragmentary sectional view, partly in elevation, showing the mechanism support arrangement and tub gyration limiting device for use with the improved roller drive mechanism of this invention, said View being shown in a stable tub situation;

FIGURE 6 is a fragmentary sectional view similar to FIGURE 5 showing the flexure situation of the mechanism support when the tub is gyrating; and

FIGURE 7 is a sectional view taken along line 7-7 in FIGURE 5 and showing the gyration limiting device in a stable tub position (solid line) and a transitory gyrating tub position (phantom line).

For use with this invention and with reference to FIGURE 1, a clothes washer 20 is comprised of a control housing assembly 22 and a casing 24. The casing 24 is generally divided into a mechanism portion or compartment 26 and a washing compartment or Water container chamber 28. A generally centrally located bulkhead 30 separates the mechanism compartment 26 from the water container chamber 28 which is further bounded 'by a cylindrical water container wall 32. Within the water container 32 is a spin tub 34 having a top opening 36 and a plurality of centrifuging outflow ports 38. The ports 38 are designed to permit the egress of water from the tub 34 when the tub is rotated at high speed. For filling the tub 34 with water a conventional water supply system may be provided with a hot and cold water solenoid operated mixing valve 42 which is manifolded into a mixed water supply conduit 44 terminat ing at a chute overlying the opening 36 of the tub. Within the tub 34, an agitator or pulsator 48 of the type taught in the patents to Bullock 3,132,500 and Walton 3,132,502 is adapted to reciprocate vertically to circulate or agitate the water admitted through the water supply conduit 44. Thus, clothing placed within the tub 34 is washed as the agitating action of the pulsator 48 forces surging toroidal currents of washing fluid and detergent through the fabric. Conventional sequential operating timer means, shown generally at 50 on the control housing 22, may be included selectively to admit water through the supply conduit 44, to spin the tub 34 and to vertically reciprocate the agitator or pulsator 48.

Roller drive mechanisms for selectively spinning a tub and reciprocating or oscillating an agitator are taught in the aforementioned Brucken patent, and in Sisson Patents 3,060,712 issued Oct. 30, 1962, and 3,165,911 issued Ian. 19, 1965, and assigned to the same assignee as this invention. This invention is directed to an improved slipping clutch and mechanism support arrangement for use in combination with roller drive mechanism, one of which is shown generally at 51 in FIGURE 1, said arrangement providing for controlled slipping drive during spin or motor rotation, thereby simplifying out of balance load protection for the washer and its motor.

The roller drive mechanism 51 is suspended from a stationary shaft enclosing housing portion 54 which is connected to a resilient cup-shaped support member 56 and which partially encloses a spin shaft 55 and an agitate shaft 57. The support member 56, in turn, is affixed to an opening 58 in the bulkhead 30-a suitable sealing gasket being provided to effect a Watertight connection there/between. In order to dampen excessive gyrating or swinging movement of the agitate and spin mechanisms lower end, a snubber device 69 may be used of the type taught in the concurrently filed application Ser. No. 430,- 266 filed Feb. 4, 1965.

The agitating and spinning mechanism 51 includes a /3 H.P., split phase, single speed 1725 r.p.m., four-pole reversible motor 60 with a built-in automatic reset type thermal overload protector.

The roller arrangement is of the improved type taught in the concurrently filed application Ser. No. 430,265 filed Feb. 4, 1965 wherein the motor 60 drives either a spin Wheel assembly or drum-like spin driven roller means 68 during spin or an agitate wheel or drum-like agitate driven roller means 7 0 having an angularly directed crank member 71 and pulsator arm assembly 73 for eifecting reciprocation of the shaft 57 during agitate. Interposed between the motor and the agitate wheel 7 0 is the agitate roller or idler 72, spring loaded and laterally floating in a manner (not shown) to make it self-energizing according to the concept of the Brucken patent. Similarly, a self-energizing spin roller or idler 76 lies between the motor and the spin wheel assembly 68.

In general, the spin wheel assembly 68 is provided with a spin wheel or spin driven roller 80 having an upper compartment or cavity 82 for housing a spin brake subassembly 84 and a lower compartment or cavity 86 for housing the slip clutch subassembly 88.

The spin brake subassembly 84 is of the disc type which consists of a brake plate 90 mounted on the lower end frame or support 92 of the motor, the brake lining 94 being keyed against relative rotation to the spin wheel and springs 96 and 8 which are assembled inside the cavity at the top of the spin drum. Two types of springs are used in the brake subassernbly. Two spring washers 96 are used to control the loading between the brake lining 94 and the brake plate 90 during the braking period. In addition to the springs 96, three, two-pound coil brake teaser springs 98 are circumferentially arranged about the spin wheel 80 and are used to apply a combined constant load of six pounds between the brake lining 9 3- and the brake plate 90 as the means for rapidly applying full braking force at the conclusion of spin-a friction washer 99 limiting the upward travel of the spin wheel assembly 68 and thus the amount of braking force applied.

The improved slip clutch of this invention is provided in the spin wheel assembly 68 (FIGURES 2 and 3). This clutch consists of the clutch, plate 100 between two clutch linings 1G2, 164 assembled inside the bottom cavity 86 of the spin wheel. The clutch plate is keyed to the spin brake cam 196 by notches 108 in the brake plate which fit over bosses 110 on the brake cam. A rubber isolator 112 is assembled between the keyed connection of the clutch plate and the spin brake cam to dampen the transmission of sound from the clutch to the washer spin shaft. The clutch linings have teeth 114 which mate with slots 116 inside the spin wheel. A coil spring 118, retained at the top by an upper spring retainer 120, is mounted inside the spin wheel below the clutch lining 104. The entire clutch assembly is held in place in the bottom of the spin wheel by the clutch retainer 121. The coil spring 118 is compressed between the clutch retainer and the lower lining of the clutch so that spring pressure is applied on the clutch lining. Sleeve type spacers 124 are assembled on the clutch retainer mounting screws 126 between the retainer and the bottom of the spin wheel. These spacers serve to position the retainer so that the desired compression of the coil spring is obtained when the retainer mounting screws are fully tightened. In the slipping clutch roller drive mechanism of this invention, the spring compression should be such that the clutch plate 109 will slip at load torques below maximum motor torque.

The spin wheel 80, spin brake 84 and slipping clutch 88 are mounted on the spin shaft 55. A spin roll stop 130 with ramp teeth 132 that mate with complementary teeth 134 on the spin brake cam is mounted on the spin shaft below the spin wheel assembly. The center hole of the spin roll stop is splined at 136 to mate with the splines on the lower end of the spin shaft. The entire assembly, consisting of the spin wheel 80, spin brake 84, slipping clutch 88 and spin roll stop 130 is retained on the spin shaft by a hex nut 140.

Note that the ramp teeth 132 of the spin roll stop are continuous in the selective slipping clutch roller drive, i.e., no stops at the top of the tooth ramp, the stops having been removed from the aforementioned non-slipping designs of this type to prevent braking from occurring at the slip clutch instead of at the brake. With the continuous ramp, the clutch locks itself. Braking action occurs, then, only in the brake 84 between the friction washer 94- and the brake plate 90.

The improved roller drive mechanism is equipped with a /3 H.P., split phase, single speed 1725 r.p.m., four-pole reversible motor 60 with a built-in automatic reset type thermal overload projector. Thus, the use of a slipping :lutch for the spin function of a roller drive mechanism eliminates the need for a manual reset type external motor arotector. Of course, it is within the purview of this nvention to use a two-speed motor with the slipping clutch feature where additional speeds of agitation and spin are desired. With the exception of spinning action, the operation of the slipping clutch roller drive mechanism is :he same as that taught in the patent to Sisson 3,165,911.

4 SPIN OPERATION For spin operation, the motor shaft, viewed from the bottom rotates counterclockwise and drives the spin idler 76 clockwise. As the motor starts to rotate, the floating action of the spin roller on its spacer permits the roller to be pulled by rotational force into positive contact with the surface of the spin wheel 80. Thus, the rotational torque of the motor is transmitted through the spin roller to cause the spin wheel to rotate counterclockwise.

The slip clutch linings 102, 104 rotate with the spin Wheel. The clutch plate is fastened to the brake cam 106 and the teeth of the brake cam are engaged with the teeth of the spin roll stop which in turn is splined onto the lower end of the spin shaft.

The amount of torque required to start the spin shaft and tub rotating and accelerate the tub to operating speed is greater than the torque required to maintain operating tub speeds after acceleration.

The pressure of spring 118 on the clutch linings 102, 104- is adjusted so that the clutch plate will slip between the clutch linings when a specified torque load is applied on the spin wheel, thus limiting the amount of torque that can be transmitted through the clutch to drive the spin shaft and tub. Distinguishing from the impact clutch of the Sisson Patent 3,165,911 wherein slip occurs above maximum motor torque (say above 100 inch-pounds), the clutch in the slipping drive slips below maximum motor torque (say less than 30 inch-pounds).

Thus, as the washer motor starts at the beginning of the spin period, the clutch plate slips, permitting the motor and spin wheel to accelerate to operating speed almost instantly. The torque transmitted through the clutch is sufiicient to start rotation of the spin shaft and tub and gradually accelerate them to operating spin speeds. As the tub approaches full spin speeds, the torque load on the clutch is reduced. At this point, the clutch plate stops slipping for the balance of the spin period.

BRAKE OPERATION The motor is tie-energized at the completion of the spin period. The motor shaft and rotor assembly, lighter in weight than the washer tub, decelerates faster than the tub.

As the motor decelerates, the spin roller 76 imposes a frictional drag on the spin wheel. This drag, in addition to the constant 6-pound load between the brake lining 94 and the brake plate 99, causes the spin wheel to decelerate.

Since the washer tub decelerates slower than the spin wheel, the spin shaft 55 turns inside the spin wheel 80. This causes the spin wheel brake cam 106 to ride up on the teeth 132 of the spin roll stop 130, thus moving the spin wheel upward until it stops in contact with a-thrust washer 99 mounted on the spin shaft above the spin wheel. As the spin wheel stops its upward travel, the action of the brake cam riding up on the spin roll stop, without restriction, serves to apply pressure on the clutch plate 100, preventing the clutch plate from slipping during the brake period.

The upward movement of the spin wheel causes an increase in the load between the brake lining 94 and the brake plate 90. The increase in load causes the two spring washers 96 in the top of the spin wheel to compress and impose a spring load on the brake lining. Since the upward movement of the spin wheel is limited by the thrust washer 99 on the spin shaft, a constant maximum load is imposed between the brake lining and the brake plate until the spin shaft and the washer tub are brought to a complete stop.

OUT OF BALANCE LOAD PROTECTION Out of balance load protection for washers equipped with the slipping clutch roller drive mechanism is provided by the slipping clutch. In view thereof, the mechanical out-of-balance load trip device of the type taught in Sisson Patent 2,882,360 and heretofore used with roller drive mechanisms is eliminated.

In the event that the load in the washer tub is badly out of balance at the start of spin operation, the tub will travel in an orbit as it rotates and the entire moving mass system will gyrate about a point generally at the flexible support 56. This orbital motion causes an increase in the amount of torque required to accelerate the tub to full spin speed, which results in an increased load on the clutch plate. Under these conditions, the amount of torque that can be transmitted through the clutch is insufficient to accelerate the tub to spin speed high enough to cause objectionable cabinet vibration.

The Washer timer 50 continues to advance through the complete time cycle and all functions of the washer except for the reduced spin speed are normal.

Cooperating with the slipping clutch drive is the support arrangement for the dynamically moving mass system comprised of the spin tub 34 and the roller drive mechanism 51 therebelow. The mechanism support hat 56 is relatively softer than its counterpart in earlier design roller drive mechanisms. More particularly, the mechanism support hat 56 is softened sufficiently to reduce the critical speed of the spin tub 34 to approximately 150 rpm. as compared with 200 to 250 rpm. in the prior structures. The softening of the hat lowers the spring rate so that with a given weight of the suspended mass, the frequency of response is reduced, thereby resulting in a lower critical speed. This, together with the restraint of a slipping clutch, reduces the forces transmitted to the cabinet through the bulkhead on which the moving mass is supported. In other words, the energy absorbed by the spring rate of the support hat 56 and the slip of the clutch substantially equals the transmitted force or unbalance inertia load. With the clothes washer of this invention, the resultant inertia load is always less than the force necessary to move the clothes washer cabinet 24. To generalize, it can be said that the softer the support hat 56, the less will be the requirement for clutch slip.

During an unbalanced spin situation, the gyrations of the moving mass, including the spin tub, are limited at the support hat 56, by a restraining roller assembly 159. The roller assembly is comprised of a support bracket 152 fastened to the support housing 54 of the agitating and spinning mechanism 51. A retainer disc 154 fastened at 155 forms an annular channel or groove for cradling a nylon ring 158. If the gyrations of the moving mass become sufficiently severe to effect the situation shown in FIGURE 6, the nylon ring 158 will bump into the reinforced side of the support hat 56 and rotate in its annular channel as a means to stabilize and limit the gyrations of the tub.

It should now be seen that an improved and simplified roller drive mechanism has been provided wherein the load torque on the spin shaft is balanced against the drive torque of the slip clutch in cooperation with a relatively soft support structure for the moving mass system, thereby to reduce the critical speed of the clothes washer provided with this invention and eliminate the need for complicated out of balance load trip mechanism.

While the embodiment of the present invention as herein disclosed constitutes a preferred form, it is to be understood that other forms might be adopted.

What is claimed is as follows:

1. In combination, a washing machine having an agitator and a spin tub, means for moving said agitator and rotating said tub, said means comprising a support means, a reversible motor, an agitate shaft, a spin shaft concentric with said agitate shaft, a shaft housing affixed to said support means and enclosing said shafts, an agitate drum rotatably supported on said support means and having an angularly directed crank member, a spin drum relatively axially threadedly supported on said spin shaft, a pulsator arm assembly having one end universally movably connected to said agitate shaft and another end relatively rotatably connected to said crank member, roller drive means drivably connected to said motor and having a first member adjacent said spin drum and a second member adjacent said agitate drum, and slip clutch means in said spin drum between said first member and said spin shaft, said slip clutch means including means slippingly responsive to a torque below the maximum torque of said motor for slipping to prevent out of balance loads in said spin tub from being rotated to spin speeds above the critical speed, said support means including yieldable means having a sufiiciently soft spring rate in cooperation with the slip in said slip clutch means to reduce the frequency of response thereof and thereby effect a critical speed of rotation for said spin tub when rotating with an unbalanced load which will be below that speed at which said washing machine will be moved in response to the rotation of said unbalanced load.

2. In combination, a washing machine having an agitator and a spin tub, means for moving said agitator and rotating said tub, said means comprising a support means, motor means, agitate shaft means, spin shaft means, shaft housing means connected to said support means and enclosing said shaft means, an agitate drum rotatably supported on said support means and having an angularly directed crank member, a spin drum relatively axially threadedly supported on said spin shaft means, a pulsator arm assembly having one end universally movably connected to said agitate shaft means and another end relatively rotatably connected to said crank member, roller drive means drivably connected to said motor means and having a first member adjacent said spin drum and a second member adjacent said agitate drum, and slip clutch means between said first member and said spin shaft means, said slip clutch means including means slippingly responsive to a torque below the maximum torque of said motor means for slipping to prevent out of balance loads in said spin tub from being rotated to spin speeds above the critical speed, said support means including yieldable means having a sufliciently soft spring rate in cooperation with the slip in said slip clutch means to reduce the frequency of response thereof and thereby effect a critical speed of rotation for said spin tub when rotating with an unbalanced load which will be below that speed at which said washing machine will be moved in response to the rotation of said unbalanced load.

3. The combination of claim 2 wherein said yieldable means includes means for limiting the gyrations of said spin tub.

4. The combination of claim 3 wherein at least a portion of the limiting means is rotatable.

5. In combination, a washing machine having a rotatable tub, means for rotating said hub, said means comprising a support means, motor means, spin shaft means carried by said support means, a spin drum supported on said spin shaft means, drive means drivably interconnecting said motor means and said spin drum, and slip clutch means for said spin drum between said drive means and said spin shaft means, said slip clutch means including means slippingly responsive to a torque below the maXimum torque of said motor means for slipping to prevent out of balance loads in said rotatable tub from being rotated to spin speeds above the critical speed, said support means including yieldable means having a sufficiently soft spring rate in cooperation with the slip in said slip clutch means to reduce the frequency of response thereof and thereby effect a critical speed of rotation for said rotatable tub when rotating with an unbalanced load which will be below that speed at which said washing machine will be moved in response to the rotation of said unbalanced load.

6. In combination, a washing machine having a spin tub and a roller drive mechanism for rotating said tub, said mechanism comprising (a) a support means including a resilient mechanism support housing at the top thereof, a brake plate means at the bottom thereof and a shaft housing therebetween,

(b) a reversible motor supported by said support means,

(e) spin shaft means connected to said tub,

((1) said shaft housing enclosing at least a portion of said spin shaft means,

(e) a spin drive assembly relatively axially movably supported on said spin shaft means between an upper position and a lower position and including a spin drum, a spin brake subassembly in a dished out upper portion of said spin drum and a slip clutch subassembly in a dished out lower portion of said spin drum,

(f) said spin brake subassembly including spring biased means rotatable with said spin drum and adapted to frictionally brakingly engage said brake plate means for stopping the rotation of said tub when said spin drive assembly is in its upper position and including means for limiting the amount of braking engagement,

g) said slip clutch subassembly interposed between said spin drum and said spin shaft means for providing a selectively slipping driving connection therebetween and including clutch friction means connected to said spin drum and brake cam means drivably connected to said spin shaft means and having cam means adapted to move said spin drive assembly between said upper and lower positions when said brake cam means rotates relative to said spin shaft means,

(h) said brake cam means including clutch plate means frictionally engaging said clutch friction means and adapted to slip relative to said clutch friction means at a predetermined driving torque less than the maximum torque of said motor,

(i) and a spin roller adapted for self-energizingly positioning itself in power transmitting relationship between sad motor and said spin drum when said motor is operating in one direction,

(j) said slip clutch subassembly including means for controlling the frictional engagement of said clutch friction means with said clutch plate means thereby to control the slip between the spin drum and the spin shaft means at said predetermined driving torque,

(k) said last named means including retainer means axially fixed relative to the spin drum and coaxial therewith and having a coil spring means between said retainer means and said clutch friction means for biasing said clutch friction means into engagement with said clutch plate means and with a sufficient pressure when said motor is operating in said one direction to permit said clutch plate means to slip relatively to said clutch friction means at all driving torque requirements below the maximum torque of said motor.

7. The combination of claim 6 wherein said slip clutch iubassembly includes means between said clutch plate neans and said cam means for isolating and dampening vibrations.

8. The combination of claim 6 wherein said resilient nechanism support housing has a sufficiently soft spring "ate in cooperation with the slip in said slip clutch sublssembly to reduce the frequency of response thereof and affect a critical spin tub speed of approximately 150 rpm. vhen said spin tub is gyrating in response to an unbal- LIICEd load.

9. The combination of claim 8 including means in said nechanism support housing for limiting the extent of gyraion by said spin tub, said means including a rotatable ing carried by said shaft housing and rollingly engaging he inside of said mechanism support housing to limit the xtent of lateral movement of said shaft housing.

10. The combination of claim 8 including means for snubbing the gyrations of said spin tub at a point below said resilient mechanism support housing.

11. In combination, a washing machine having a tub and a roller drive mechanism for rotating said tub, said mechanism comprising (a) a support means including a resilient mechanism support housing at the top thereof and a shaft housing therebelow,

(b) a motor supported by said support means,

(c) spin shaft means connected to said tub,

((1) said shaft housing enclosing at least a portion of said spin shaft means,

(e) a spin drive assembly on said spin shaft means including a spin drum and a slip clutch subassembly in a dished out lower portion of said spin drum,

(f) said slip clutch subassembly being interposed between said spin drum and said spin shaft means for providing a selectively slipping driving connection therebetween and including first means connected to said spin drum and second means drivably connected to said spin shaft means,

(g) said second means including means frictionally engaging said first means and adapted to slip relative to said first means at a predetermined driving torque less than the maximum torque of said motor,

(h) and a spin roller adapted for self-energizingly positioning itself in power transmitting relationship between said motor and said spin drum when said motor is operating,

(i) said slip clutch subassembly including means for controlling the frictional engagement of said first means with said frictionally engaging means thereby to control the slip between the spin drum and the spin shaft means at said predetermined driving torque,

(j) said last named means including retainer means axially fixed relative to the spin drum and coaxial therewith and having a coil spring means between said retainer means and said first means for biasing said first means into engagement with said frictionally engaging means with a sufiicient pressure when said motor is operating to permit said frictionally engaging means to slip relatively to said first means at all driving torque requirements below the maximum torque of said motor.

12. An agitating and spinning mechanism comprising (a) a support means including a resilient mechanism support housing at the top thereof, a brake plate means at the bottom thereof and a shaft housing therebetween,

(b) a reversible motor supported by said support means,

(0) spin shaft means adapted for connection to a rotatable tub,

((1) said shaft housing enclosing at least a portion of said spin shaft means,

(e) a spin drive assembly relatively axially movably supported on said spin shaft means between an upper position and a lower position and including a spin drum, a spin brake subassembly in a dished out upper portion of said spin drum and a slip clutch subassembly in a dished out lower portion of said spin drum,

(f) said spin brake subassembly including spring biased means rotatable with said spin drum and adapted to frictionally brakingly engage said brake plate means for stopping the rotation of said tub when said spin drive assembly is in its upper position,

(g) said slip clutch subassembly being interposed between said spin drum and said spin shaft means for providing a selectively slipping driving connection therebetween and including first means connected to said spin drum and second means drivably connected to said spin sha-ft means and having cam means adapted to move said spin drive assembly between said upper and lower positions when said second means rotates relative to said spin shaft means,

(h) said second means including means frictionally engaging said first means and adapted to slip relative to said first means at a predetermined driving torque less than the maximum torque of said motor,

(i) and a spin roller adapted for self-energizingly positioning itself in power transmitting relationship between said motor and said spin drum when said motor is operating in one direction,

(j) said slip clutch subassembly including means controlling the frictional engagement of said first means with said frictionally engaging means thereby to control the slip between the spin drum and the spin shaft means at said predetermined driving torque,

(k) said last named means including retainer means axially fixed relative to the spin drum and coaxial therewith and having a coil spring means between said retainer means and said first means for biasing said first means into engagement with said frictionally engaging means with sufiicient pressure when said motor is operating in said one direction to permit said frictionally engaging means to slip relatively to said first means at driven torque requirements below the maximum torque of said motor.

13. An agitating and spinning mechanism comprising (a) a support means including a resilient mechanism support housing at the top thereof and a shaft housing therebelow,

(b) motor means supported by said support means,

() spin shaft means adapted for connection to a rotatable tub,

(d) said shaft housing enclosing at least a portion of said spin shaft means,

(e) a spin drive assembly on said spin shaft means including a spin drum, and a slip clutch subassembly,

(f) said slip clutch subassembly being interposed between said spin drum and said spin shaft means for providing a selectively slipping driving connection therebetween and including first means connected to said spin drum and second means drivably connected to said spin shaft means,

(g) said second means including means frictionally engaging said first means and adapted to slip relative to said first means at a predetermined driving torque less than the maximum torque of said motor,

(h) and a spin roller adapted for self-energizing positioning itself in power transmitting relationship between said motor and said spin drum when said motor is operating,

(i) said slip clutch subassembly including means controlling the frictional engagement of said first means with said frictionally engaging means thereby to control the slip between the spin drum and the spin shaft means at said predetermined driving torque,

(j) said last named means including retainer means axially fixed relative to the spin drum and coaxial therewith and having spring means between said retainer means and said first means for biasing said first means into engagement with said frictionally engaging means with sufiicient pressure when said motor is operating to permit said frictionally engaging means to slip relatively to said first means at driven torque requirements below the maximum torque of said motor.

References Cited by the Examiner UNITED STATES PATENTS 1,373,810 4/1921 Hansen 6430 2,380,595 7/1945 Hertrich 643O X 2,859,877 11/1958 Sisson 68-23 X 3,165,911 1/1965 Sisson 68-23 WILLIAM 1. PRICE, Primary Examiner. 

5. IN COMBINATION, A WASHING MACHINE HAVING A ROTATABLE TUB, MEANS FOR ROTATING SAID HUB, SAID MEANS COMPRISING A SUPPORT MEANS, MOTOR MEANS, SPIN SHAFT MEANS CARRIED BY SAID SUPPORT MEANS, A SPIN DRUM SUPPORTED ON SAID SPIN SHAFT MEANS, DRIVE MEANS DRIVABLY INTERCONNECTING SAID MOTOR MEANS AND SAID SPIN DRUM, AND SLIP CLUTCH MEANS FOR SAID SPIN DRUM BETWEEN SAID DRIVE MEANS AND SAID SPIN SHAFT MEANS, SAID SLIP CLUTCH MEANS INCLUDING MEANS SLIPPINGLY RESPONSIVE TO A TORQUE BELOW THE MAXIMUM TORQUE OF SAID MOTOR MEANS FOR SLIPPING TO PREVENT OUT OF BALANCE LOADS IN SAID ROTATABLE TUB FROM BEING ROTATED TO SPIN SPEEDS ABOVE THE CRITICAL SPEED, SAID SUPPORT MEANS INCLUDING YIELDABLE MEANS HAVING A SUFFICIENTLY SOFT SPRING RATE IN COOPERATION WITH THE SLIP IN SAID SLIP CLUTCH MEANS TO REDUCE THE FREQUENCY OF RESPONSE THEREOF AND THEREBY EFFECT A CRITICAL SPEED OF ROTATION FOR SAID ROTATABLE TUB WHEN ROTATING WITH AN UNBALANCED LOAD WHICH WILL BE BELOW THAT SPEED AT WHICH SAID WASHING MACHINE WILL BE MOVED IN RESPONSE TO THE ROTATION OF SAID UNBALANCED LOAD. 